Less than a mile off a county road in Ivanhoe near the Black River, federal drug agents and local authorities found exactly what their informant had promised.

"We saw what looked like, as far as you could see, marijuana plants," said Drug Enforcement Administration agent Michael Franklin.

There were about 2,400 in all, surrounded by a makeshift camp where the growers had illegally squatted on private property, setting up a generator and pump to tap the river for irrigation. The camp, which had been recently inhabited, contained a tarp shelter, canned fuel, drinking water, toiletries and old clothing, some of it camouflage.

Authorities staked out the "grow" for two days waiting for the marijuana farmers to return. They didn't. It was just as well, Franklin said.

"The people we were really focusing on were not the guys tending the field. The guys bankrolling the field were the target," he said.

Because the investigation into the June 2009 seizure is still ongoing, the DEA would not divulge further details. But Franklin said the case is one in a growing list of cartel-linked busts he is seeing in largely rural southeastern North Carolina. The area's Latino population has grown considerably in the past 20 years, and authorities say cartel operatives use Latino communities as cover.

"While the majority of (Latino residents in the area) are hardworking people like anyone else, it's an opportunity for the cartels to have their foot soldiers do their thing, too," Franklin said. Based in Wilmington, he is resident agent in charge of 14 counties.

News of cartel machinations are common in cities near the border, such as Phoenix, and the far-flung drug hubs of New York, Chicago or Atlanta, but smaller towns bring business, too. In unsuspecting suburbs and rural areas, police are increasingly finding drugs, guns and money they can trace back to Mexican drug organizations.

The numbers could rise in coming years. The Justice Department's National Drug Intelligence Center estimates Mexican cartels control distribution of most of the methamphetamine, heroin and marijuana coming into the country, and they're increasingly producing the drugs themselves.

In 2009 and 2010, the center reported, cartels operated in 1,286 U.S. cities, more than five times the number reported in 2008. The center named only 50 cities in 2006.

"I'm not saying Mexicans come here to do crime, but Mexicans who move drugs choose to do it through areas where there are already Mexicans," he said.

Evidence of the cartels' presence in small-town America isn't hard to find. Take the 66 kilos of cocaine found in a warehouse in North Kingstown, Rhode Island, in February 2011. Or the Wyoming, Michigan, man denied bail on drug charges last year because he had alleged cartel connections. Or consider that a surge of Mexican black tar heroin into Ohio pushed the price per kilogram down from $50,000 in 2008 to $33,000 in 2009.

It isn't always so clear cut, Franklin said. The DEA has several cases where cartel activity is suspected, but agents are unable to draw definitive links.

In fact, so much of the Wilmington bureau's caseload involves suspected cartel activity that Franklin three years ago set up a tip line, which it now promotes on large Spanish-language radio stations across the state.

The 30-second spot urges listeners to call 1-855-663-7642 if they know of any illicit activity involving drugs or money, assures them calls are confidential and offers rewards for useful information.

Spanish-speaking operators answer calls to the tip line, vet the information and quickly inform the DEA when a tip seems viable. Callers range from good citizens sick of dealers in their neighborhoods to suspicious relatives to underpaid couriers looking to turn informant.

"Sometimes it's just a report that some dude is talking s**t at parties," Franklin said.

There are also those who are terrified to return home to face cartel justice, where a swift decapitation could be a merciful resolution. Franklin calls it "ajuste de cuentas," a term he learned while stationed in Mazatlan, Mexico. Meaning "reckoning" or "balancing the books," it's an order to take out a subordinate who loses money or drugs, and it's usually not pretty.

"If they lose a load of dope, how could they pay back $3 million in cocaine when their fee was only $5,000 to move it? That guy comes to our side and we seize that much cocaine, he's going to make a lot more money with us," Franklin said.

DEA agents recently allowed CNN to accompany them on a seizure generated by the tip line.

It was just after 8 on a February night, and a mild, chilly rain fell on the SUV as we waited, watching "30 Rock" on a smartphone and snacking on peanuts and beef jerky in lieu of supper.

At the house in an unassuming High Point neighborhood, authorities found trash bags with 115 pounds of marijuana.

Also in the High Point home was a ledger and a shoebox containing $76,899 in cash, the DEA says.

It's not all shootouts, high-speed chases and kicking down doors, as Hollywood tells it. There's a lot of waiting, watching, listening -- estimating the perfect time to make a move.

At about 9 p.m., the call came. Franklin directed us to an unassuming middle-class neighborhood a quarter-mile away. The exact location: a one-story white house with a "Neighborhood Watch Community" sign in a picture window by the front door.

When we arrived, shadows moved back and forth behind the lattice wall of a carport as police and DEA agents entered and exited the house. Franklin told us that authorities had just found two men inside with 115 pounds of marijuana bricks in a black trash bag.

They also found a ledger suggesting there was more weed at one time. A shoebox containing $76,899 seemed to confirm it.

Nearby residents seemed clueless about the drugs being moved through their community. After the raid, one concerned and curious neighbor told police there had been break-ins in the area, but that it's generally safe.

At the house where police found the marijuana, the neighbor said, four men had moved in about two weeks prior, but she never saw any moving trucks or furniture, which made her suspicious. She was appalled to learn of the drug arrests and vowed to voice her disapproval to the rental agency that leased the house to the suspects.

Although the two men arrested were Latino, nothing during the DEA's surveillance or post-arrest interviews suggested they were linked to any cartel, Franklin said. One of the men carried a driver's license from Washington state, the other from California.

Franklin said he has seen local cases that investigators were able to tie to the Gulf Cartel and Los Zetas -- and there was the 2009 marijuana raid in Ivanhoe -- but drawing a cartel link typically isn't easy.

In recent years, though, law enforcement agencies have been able to put names to some of the cartels they've chased in coordinated strikes.

Operation Xcellerator (Sinaloa Cartel) and projects Coronado and Delirium (La Familia Michoacana) have put thousands of cartel types behind U.S. and Mexican bars. Seizures included tons of marijuana and cocaine, hundreds of pounds of methamphetamine, guns, vehicles and about $100 million, all linked to specific cartels.

Such operations are anomalous. Cartels like their anonymity, according to police and analysts across the nation. Even if couriers or dealers know which cartel they're working for, they're often too scared to say.

In August 2011, the DEA uncovered 90 kilograms of cocaine buried under a barn in rural Robeson County, North Carolina.

Others are so far down the supply chain that they don't know who they're peddling for. There are also instances where cartel operatives co-opt existing street gangs who already controlled their respective markets -- and seasoned drug dealers know better than to ask a lot of questions about the source of their drugs.

"They're not so kind as to say, 'This dope came from Los Zetas,' " said special agent Jeffrey Scott of the DEA's Seattle bureau, but "if you follow the bread trail far enough back, you're going to hit a cartel phone, courier or money pickup."

Mount Vernon, Monroe, Tacoma and Kelso -- small to midsize cities in Washington state with large Hispanic populations and easy access to interstates -- have seen similar scenarios to those in southeastern North Carolina. The cities are by no means "infiltrated or controlled" by cartels, Scott said, but there have been major drug cases there since 2009.

Battle of Wilmington

Wilmington certainly fits the bill for a cartel sub-hub. It has the obligatory major thoroughfare, I-40, which runs all the way to Barstow, California, 2,500 miles away. Wilmington's Latinos constitute only around 6 percent of the city's population, but outlying counties like Cumberland, Sampson and Duplin have watched their Latino numbers skyrocket in the past two decades. Employment -- construction in the city and farming in the counties -- is the big draw.

On its face, the 273-year-old, largely white port city wedged between Wrightsville Beach and the Cape Fear River appears an unlikely front in the Mexican drug war.

Bars, restaurants, shops and Spanish moss-draped oaks pepper the quaint downtown, which is bookended by a community college and a century-old Catholic church. Its weather and tidy beaches draw plenty of tourists and retirees.

Thousands of educators, UNC-Wilmington students, government workers, surfers and military personnel call Wilmington home. The regional medical center provides almost 5,000 jobs, while GE, Progress Energy, Corning, Verizon, Walmart and International Paper are also big employers. The pharmaceutical industry also brings thousands of jobs to the city, making Wilmington a player in the legal drug trade as well.

There are seedy parts of town and Wilmington has its share of crime, as does any city of 100,000, but Mexican cartels? The ones that hang journalists from bridges and torch packed casinos?

The DEA drug operations also turn up guns. On top is a .50-caliber sniper rifle stolen from a Marine at Camp Lejeune.

Wilmington residents shake their heads. Not here. Couldn't be here.

It's a microcosm of what's happening in the country, as cartels quietly begin operating anywhere that lends them a competitive advantage in a market that contains about 4 percent of the world's population yet consumes roughly two-thirds of its illegal drugs.

Phil Jordan, a retired agent and former head of the DEA's El Paso, Texas, Intelligence Center, said the cartels' operations are much like that of chain retail businesses. As the cartels increasingly control the supply and distribution of their product, they concentrate employees where there is demand -- which in the U.S. is pretty much everywhere.

"The thing that triggered the mass infiltration into the United States' smaller communities is that methamphetamine has been introduced as a poor man's cocaine," he said.

Since the 1980s, Mexican cartels have smuggled massive amounts of Colombian cocaine into the U.S., but they were often paid in drugs and most of the money had to be sent back to kingpins in Medellin, Cali, Barranquilla or Valle de Cauca.

Meth presented an opportunity to keep all the profits, Jordan explained. Mexican cartels in the 1990s began taking over methamphetamine production from U.S. biker gangs, who had largely controlled the trade through the 1980s. A U.S. crackdown on meth's precursor chemicals -- namely ephedrine, pseudoephedrine and phenylpropanolamine -- culminated in the Combat Methamphetamine Epidemic Act that became law in 2006.

Though the act was designed to disrupt meth production, it solidified the cartels' grip on the market. The cartels needed operatives in place to move the meth. Once those distributors were in place, Jordan said, it became easier to move the cartels' other specialties.

"If you can find Mexican methamphetamine in a community, you'll find the heroin and cocaine," he said.

Yet despite the increasing cartel presence in America, acts of wanton violence like those occurring south of the border aren't so common stateside.

Five pounds of meth were seized in Columbus County in July 2011. A former agent says meth opened doors for the cartels.

Bowden, whose books reflect reporting from both sides of the border, said the cartels realize it's not smart to exact a Mexican brand of violence in the United States.

The reason is twofold, Jordan said: Cartels fear American law enforcement agencies because they respond to violence more swiftly and forcibly than do their Mexican counterparts, and "since the U.S. is the primary consumer, the cartels will try and avoid disturbing the hand that feeds them."

"America is not a safe haven for those that betray the cartels. They will seek you and kill you," he said, adding that average citizens rarely have to worry. "For the most part, the killing fields of Mexico will not transfer to the U.S., except for those that have betrayed the cartels."

In the U.S., the cartels rely more on bribery than brutality. The Department of Homeland Security in 2009 and 2010 reported record numbers of investigations (576 and 870) into U.S. Border Patrol agent misconduct.

Despite the violence south of the border and the corruption north of it, the periodical noted that violent and property crimes in Southwest border towns generally decreased between 2005 and 2009.

"No mass murders, piles of corpses in the middle of highways, decapitations, mutilations, incinerations or tortured bodies hanging in urban bridges have been registered in the U.S. side of the border," the periodical states.

The death of enforcer Ramon Arellano Felix of the Arellano Felix cartel taught Franklin a lesson about sources.

Mazatlan offers lesson

Agent Franklin is familiar with scenes on both sides of the border. From 2001 to 2004, before he took the helm at Wilmington in 2007, he was stationed in the Pacific Coast city of Mazatlan, in Mexico's cartel-ridden Sinaloa state.

Back then, the cartels were operating in the U.S., but their dealings were largely concentrated along the border and in major cities. As drug trafficking increased with the spike in immigration, Franklin said, cartels found more and more ways to exploit their most profitable market.

Franklin's duties in Mazatlan often involved working with Mexican authorities on interdiction efforts. Many of them, including 2001's Operation Trifecta, which spanned 19 months from 2001 to 2003, involved maritime smuggling.

Trifecta began after a source tipped off authorities to more than 10 tons of cocaine on a fishing vessel, the Macel, off the Pacific Coast of Mexico. The operation yielded 240 arrests in the U.S. and in Mexico, along with tons more drugs, mostly marijuana and cocaine.

The operation's success helped Franklin realize the importance of sources. An incident the year after the Macel seizure solidified the notion.

In February 2002, a shootout after a traffic stop in Mazatlan left three men, one of them a police officer, dead in the streets. Police and local newspapers identified one of the dead as Jorge Perez Lopez, the name on the man's fake ID.

"Ohh, the value of the source!" Franklin wrote in an e-mail containing newspaper reports of the shootout.

In 2009, the DEA got a tip that a refrigerator being delivered to a trailer in Warsaw, North Carolina, contained cocaine.

Those lessons in Mazatlan are one of the reasons Franklin and his bureau hold sources so dearly today. It also was an impetus in the creation of the Spanish tip line.

Simple as it may seem, the tip line has provided some of the biggest cases for the Wilmington bureau in recent years, many of them with suspected links to cartels.

Franklin did not want to divulge exact numbers, nor could he speak about more recent, ongoing cases, but he said the tip line is responsible for the seizures of tons of marijuana, hundreds of kilograms of various illicit powders, dozens of weapons and millions in currency. Among the seizures in North Carolina:

• A commercial-grade refrigerator concealing 23 kilograms of cocaine was intercepted at a trailer park in Warsaw in September 2009. It had been shipped from Brownsville, Texas. Inside the Warsaw mobile home, police found cutting agents, packing materials, a cocaine press and a loaded handgun with its hammer cocked. Two Mexican nationals were arrested.

• A March 2010 drug and weapon seizure in Duplin and Sampson counties turned up an AK-47 as well as a .50-caliber sniper rifle that had been reported stolen from a Marine at nearby Camp Lejeune. Two Mexican nationals were arrested.

• Five pounds of methamphetamine were seized in Columbus County in July. One Mexican national was arrested.

• A pair of 2011 raids in Robeson County resulted in the seizure of 118 kilos of cocaine and more than $550,000. In the second of those busts in August, officers dug up 90 kilograms of cocaine buried under a shed on a farm.

• In September, nearly $660,000 was seized in a seedy Robeson County hotel room.

Some seizures, like a 2-kilogram meth bust in Brunswick County in January, may seem small, but they count as huge successes for local law enforcement partners.

Agents also found in the trailer a press for repackaging cocaine after it's been processed with cutting agents.

To agents' dismay, there was also a loaded handgun -- with its hammer cocked -- found during the search of the trailer.

Tip line calls don't always prove so fruitful. Shortly after the High Point raid, agents received information that led them to a location near Raeford. We followed Franklin for two hours before waiting at a nearby gas station for instructions.

It was about 1 a.m. when Franklin called to say the surveillance had gone cold. After a long day -- 19 hours for some agents -- everyone headed home.

The next day, that investigation hadn't moved anywhere, but agents had a bead on a La Familia Michoacana member long wanted for cocaine and gun crimes. Franklin instructed me to drive to Supply, North Carolina, and wait. Agents later decided to make their move the next day.

In the morning, Franklin met me and the DEA handler at a Hardee's in Supply to say it was a case of mistaken identity. Agents had been watching the wrong guy the night before.

Such mistakes aren't unusual, Franklin said. Though the tip line has allowed the bureau to cultivate well-placed sources, it also has sent agents on wild goose chases. The quality of the information varies.

"We invest most in what's going to get the biggest bang," Franklin said. "You've got to kiss a lot of frogs to find a prince."

Asked if the good information is worth the false calls, Franklin laughed and said, "Two longball-hitting informants can keep you busy for days -- days and nights."

At the $1,000 a month the DEA pays four radio stations to air the ad a few times every other week, the tip line has already paid for itself for the rest of Franklin's life. The 115 pounds of marijuana in High Point alone could pick up that tab.